None
Not applicable.
The present invention relates generally to casting metals and more particularly to the foundry core/resin shapes wherein the resinous binder and some additives emit smoke during metal casting operations.
Commercial foundries have trouble regulating the amount of visible smoke emitted from cured core/mold packages when molten ferrous or non-ferrous metals are poured into the shapes. The molten metals cause the aggregate mixes, containing a variety of common foundry resin compositions, to burn. Such mixes emit a quantity of smoke, either from the burning of the resin components, water vapor, release agents, refractory coatings, or other compounds and/or additives used in the core/mold making process. Reduction of such smoke is desirable from the foundry""s standpoint, both environmentally as well as for worker health and/or safety.
Heretofore, however, foundries have not had the tools necessary for them to evaluate various foundry binder systems in a controlled or laboratory-type environment in order to adjudge the ones that emit less visible smoke at the metal pouring areas. The present invention is addressed to such need in the foundry art.
A smoke chamber for determining the amount of visible smoke emitted by a foundry core/mold resin system is composed of an elongate chamber having a proximal end, a distal end, and sides. The chamber is fitted with air inlet at its proximal end, a smoke outlet at its distal end, and a sample station disposed between the air inlet and the smoke outlet. The sample station includes a sample holder and furnace (either external or internal) for heating a sample placed in the sample holder. The chamber also includes a light assembly disposed along one side of the chamber from the sample station to the smoke outlet. A light detection assembly is disposed on a chamber side opposite the light assembly for detecting light emitted from the light assembly. The chamber may be covered or darkened in order to exclude extraneous light, which might be detected by the light detection assembly. The chamber also includes fan for drawing smoke from a heated sample placed in the sample holder to the smoke outlet. For present purposes, a xe2x80x9cfoundry core/mold resin systemxe2x80x9d includes resin components, water, release agents, refractory coatings, or other compounds, and/or additives, and aggregate used in the core/mold making process. While the inventive smoke chamber can be used to evaluate resin compositions alone, preferably the actual commercial system (resin, aggregate, and additives) will be evaluated.
The corresponding method for determining the amount of visible smoke emitted by a foundry core/mold resin system includes placing a sample in the sample holder. The sample in the sample station is heated by the furnace to pyrolize the sample. The amount of visible smoke emitted by the pyrolized sample is measured with the light detection assembly. Desirably, the light detection assembly is composed of a plurality of discrete photodetection units, each of which is in electrical connection with a recorder for recording the amount of visible light detected by each of the photodetection units. In this way, different foundry core/mold resin systems can be evaluated and compared to determine which foundry core/mold resin system has the characteristics desired for any particular use.